Electric switch



Nov. 20, 1928.

J. M: MILLER ELECTRIC SWITCH Filed Aug. 19, 1925 2 Sheets-Sheet 1 mm \\\\\\\\\\\\\\\\\\\\\\,\\\\\\\\\\\\\\\\\\\\\\\\\\\\k\\\\\\ NOV. 20, 1928. l 1,691,984

J. M. MILTLER ELECTRIC swIToH Find Aug. 19, 1925 2 sheets-sheet 2 kso' f Patented yNov., 20, 1928.

UNITED STATES 1,691,984 PATENT OFFICE.

JOHN M. MILLEE, oEDETEoI'r, MICHIGAN, AssIGNoE 0E ONE-HALE To FRANCESC.

1 y, RICHARDSON, or DETROIT, MICHIGAN.

ELECTRIC SWITCH.

.- Application tiled August 19, 1925. Serial No. 51,103.

This invention relates to electric switches, and m invention aims to utilize water or other liquid as an agency for 'controlling the amount of current from one electrode to another. `In one rform* of my invention the curn krent control is accomplishedby raising and lowering electrode relative toa body of'liquid, and in another forma bodyy of liquid 1s changed or has its level-raised to control the i current. ln' either'instance, a very sensitive and minute control 'is obtained and this is 'very desirable foryswit'ches employedk for starting kelectrically driven machinery or parts. f

l1K5 kMy invention further'aims to provide a tric'current and gradually buildsup the curf 30 rent from aminimum to amaximum supply.y 'In this forml of switch the t1me in terval may be regulated so that the switch is semi-automatic, and in this connection precludes the burningfoutof fuses, short ciruits and overloading incident to, immediate turning on of current. n f f Y My invention will be hereinafter specifically described andtlien claimed, andreference will'now be had to the drawings, wherein- Figure 1 is a vertical longitudinal sectional view of a knife or blade switch in accordance with this invention; f i ligggureZis` a planof the same;

Figure 3 is a vertical transverse sectional `View of asemi-automatic switch;

Figure 4' is a vertical longitudinal sectional view of the'same; 3 n

Figure 5 is a plan of the switch partly in horizontal section; j Y Figure 6 isa plan of a rotary switch; Figure 7 is a longitudinal sectional view of the same, and n s Figure 8 is across sectional view of the saine. -f

kReference first be had to Figures 1k and2 showing a receptacle 1 having a detachmaterial. On the cover 2, at each end thereof, are mounted connectors 8 and 4 provided with binding posts 5 and 6 respectively for leading-iii and leading-out conductors.

On the connectors 3 are apertured ears 6, and'pivotally mounted between said ears is a switch knife or blade 7 having one end thereof provided with a suitable handle 8. The opposite end of the switch knife 7 overhangs the edge of the cover 2 and is pivotally connected by a link 9 to a dash pot plunger 10.

yable cover 2, preferably made of insulation This dash pot plunger is operatively supported in a Conventional form of dash pot ll supported from the side of the receptacle l. The dash pot 11 is 'adapted to contain oil ora. suitable liquid which will flow from one end of the dash pot to the other through ports 12 in a piston 13 forming part of the plunger 10. The ports 12 may be valved or automatically controlled and the action of the dash pot is to prevent asudden closing of the switch knife 7.

On the connector 4, in the path of the switch knife 7 is a set of bladesor socket 14 to receive said knife when in a closed position.

- r1he cover 2, intermediate the connectors 3 and 4, is provided with a guide 15 for a rod 16 which has its upper end provided with a bifurcated head 17. e This head has a slot and pin connection 18 with the switch knife 7, so that pivotal movement ofthe switch knife will reciprocate the rod 16.`

On the inner end of the rod 16 is an insulator 19, and connected to the. side walls of the insulator 19, by screw bolts 20 or other fastening means, are opposed electrodes 21, preferably in the form of vertically disposed plates. ()ne of the electrodes 21, is connected by a conductor 22 to the connector 4, and the other electrode is connected by aconductor 23 to the connector 3. v

The cover 2 has a normally closed filling connection 24 so'that water 25 or a suitable liquidmay be placed in the receptacle 1. The water 25 serves as a resistance kwhen the lower ends of the electrodes 21y are iinmersed in the water and the resistance vis Varied by the area of the electrodes in l,the water. By raising and lowering the electrodes 21'the resistance is varied. As shown in Figure 1 there .is a maximum resistance, and as the electrodes are lowered this resistance gradually decreases until the switch knife 7 is closed, when there is practically a direct connection between the connectors 3 and 4 for the flow oi' current from a lead. ing-in conductor to a leading-out conductor.

The dash pot as shown will permit oit' the switch being quickly opened, but it is practically impossible to quickly close the switch. consequently there will be a gradual building up of the current between the connectors 3 and 4 of the switch.

The type of switch just. described may be considered as a reciprocatable switch, and in contradistinction to electrodes that are reciprocated, I have shown in Figures 6 to S inclusive, blade electrodes 26 mounted on and insulated from rock shaft 27 journaled in the side walls of a receptacle 28 containing water or other liquid 29 into which extend `edges of the electrodes 26. The shaft 27 has one end thereoi1 provided with a knob 30 so that it may be rocked, and to prevent aceidental rocking of the shaft 27 and at the same time establish electrical connections .with the electrodes 26, there are resilient fingers 3l which bear upon hub portions 32 of the electrodes 26. 'Ihe ingers 31 are ysup-V ported by an insulator 33 carried by the receptacle 28, and said insulator has suitable leading-in and leading-out conductors 34. lilith the electrodes 26 properly insulated troni each other and substantially semi-circular in elevation or segment shaped, Lthe shaft 27 may be rocked to place a greaterarea oi the electrodes in the liquid 29, so that the bony of liquid will serve the same purpose as the body of liquid 25 of the reciprocatable switch.

In the forms of my invention just described, the body of liquid is stationary, and the timing of the switch is a manual opera tion, but in Figures 3 to 5 inclusive, I have shown a form ot switch wherein the body ot liquid is shit'table with its flow controlled so that there may be a regulated interval oilt time between manual operation of the switch and a complete maximum current condition.

Considering Figures 3 to 5 inclusive, 35 is a suitable support, as a wall, for a wall insulator 36 attached to the wall by screws 37 or other fastening` means. The wall insulator 36 is provided with binding posts 38 for leading-in and leading-out conductors S9, and on the wall insulator are concentric contact rings 40 and 4l. Connectors 42 are employed tor connecting the binding posts 68 to the contact rings'40 and 4l, and the purpose ot these rings will hereinafter appear.

Centrally of the wall insulator 36 is a bearing 43 for a shaft 44. Mounted on the outer end of the sha-ft is a neck portion 45 of a receiving receptacle made of a frame'46 and side plates or electrodes 47 and 48. These side plates or electrodes are suitably secured to the frame 46 and cooperate therewith in forming a container or receiving receptacle 49 for a liquid 50, as water, adapted to How through a passage 51 in the neck 45 ot the receiving receptacle. Suitably attached to the neck 45 oi' the receiving receptacle is a neck 52 of a discharge receptacle 53, having a suitable i'illing connection 54. The discharge receptacle 53 has one end thereof connected by a tube 55 to one end of the receiving receptacle 49, this tubcpermitting of air lion'- ing from one receptacle to the other incident to either receptacle being filled.

T he passage 5l ot the receptacle neck 45 is controlled by a conventional form of `ported plug valve 56, and this valve may be adjusted to regulate the How of the Water or liquid 50 from one receptacle to thel other. The size ofthe passage 51 may also control the iow of liquid from one receptacle to the other, and as shown in Figure 3 the liquid in the receptacle 53 is being discharged into the receptacle 50, where it contacts vwith the side plates or electrodes 47 and establishes a variable connection between' these electrodes, with the connection increasin in area as the receiving receptacle 49 is lle The side plates or electrodes 47-are provided with extensions 57 and resilient contact members 58 and 59 engaging the contact rings 40 and 41 respectively. The contact members 58 and 59 are adapted to Wipe the contact-rings 40 and 4l when the receptacles are swung about the axis of the shaft 44, this being done to permit of the liquid in the receiving receptacle flowing back into the discharge receptacle. As a consequence of this constructive arrangement of part-s the flow of liquid from one receptacle to the other may be regulated, and set, so that after initial actuation of the switch, it may be lett alone to gradually turn on a current. This is accomplished by the level of the liquid 50 gradually rising in the receiving receptacle 49 until there is a short path of travel for the current between the electrodes48. With the valve 56 open, the body of liquid mayA be quickly returned to the receptacle 53, or the valve may be regulated vso that there is a slow return of liquid and consequently a slow opening of the switch. In either instance there is an interval between the time of manul al actuation of the switch and maximum ow of current, and it is in this connection that the switch is semi-automatic and may be regulated to increase or decrease its action.

In all forms of my swit-ch a body of liquid affords a minute and variable means of controlling the flow of a current, and there are many applications for such a switch, therefore I do not care to confine my invention to any structural details other than set forth in the appended claims. l

that I claim is:

l. A rheostat comprising a liquid receiving receptacle adapted to contain a liquid,

electrodes exposed to the liquid in said reand mounted to permit inversion, whereby liquid may flow from one receptacle to the other.

2. A rheostat comprising a liquid receiving receptacle adapted to contain a liquid,

'electrodes exposedy to the liquid in said receptacle, a liquid discharge receptacle communicating with and adapted to place liquid in said receiving receptacle to establish an electrical connection between said electrodes, 15

said receptacles being in superposed relation and mounted to permit inversion, whereby liquid may How from one receptacle to the other, stationary contact rings, and contact members carried by said liquid receiving re- 20 ceptacle and connected to said electrodes, said members being also in enggfagementy with said contact rings` y In testimony whereof I aiix my signature.

JOHN M. MILLER. 

